Multiple-cylinder engine.



PATENTED AUG. 2, 1904.

J. G. CALLAN.

MULTIPLE CYLINDER ENGINE.

APPLIOATION FILED SEPT. 4, 1903.

3 SHEETS-SHEET 1.

N0 MODEL.

IYIVGTIbOI", John G.Cal [an MMA/1%, $21

Wibrwesses:

No. 766,323. PATENTED AUG. 2, 1904. J. G. OALLAN.

MULTIPLE VGYLINDER ENGINE.

APPLICATION FILED SEPT. 4. 1903.

NO MODEL. 3 SHEETS-SHBET 2.

InVenbor: Johrw C-3.Callan.

Witnesses;

No. 766,323. PATENTED AUG. 2, 1904; J. G. GALLAN. MULTIPLE CYLINDERENGINE APPLIOATION FILED SEPT. 4, 1903.

N0 MODEL. 3 SHEETS-SHEET 3.

Wit-messes: IhVenboT, John (3.6a! Ian,

UNTTED STATES JOH N O.

Patented August 2, 1904.

PATENT OFFICE.

ELEO'JTRIO COMPANY, A CORPORATION OF NElV YORK.

MULTIPLE-CYLINDER ENGINE.

SPECIFICATION formingpart of Letters Patent No. 766,323, dated August 2, 1904.

Application filed September 4,1903. Serial No. 171,864. (No model.)

To all 1/71/0772 if nm concern Be it known that 1, JOHN G. CALLAN, a citizen of the United States, residing at Lynn, in

the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Multiple-Oylinder Engines, of which the following is a specification.

The present invention relates to that class of engines in which the cylinders are diametrically opposite each other and disposed radially about the crank-shaft.

It relates particularly to a four-cylinder engine of this type wherein a novel means is provided by which the impulses of the pistons produce either rotary motion of a singlethrow crank with the cylinders relatively stationary or rotary motion of the cylinder when the crankshaft is stationary.

The object of the invention is to increase the efficiency of this character of engine by improving the construction, whereby even balance of the working parts is obtained and the frictional losses reduced to a minimum, so as to adapt the engine to high-speed work and smooth running. The means for attaining these objects and the combination of the various parts will be more fully described hereinafter, and linally pointed out in the claims.

In the accompanying drawings, which illustrate one embodiment of my invention, Figure 1 is a plan view of an engine with por tions thereof broken away. Fig. 2 is a central vertical section through the cylinders of the engine. Fig. 3 is an enlarged perspective View of the crank with the piston-toggle-link connection and the centering member for the latter, and Fig. 4 is a diagram illustrating the toggle-linkage.

W'hile the drawings illustrate my invention as applied to an internal-combustion engine, it is not, however, limited exclusively to that type of motor. An essential condition in the design of the engine to which my invention is applicable is that of radial disposition of the cylinders with their open ends directed toward the crankshaft. In view of this the engine may operate as a gas or as a single acting steam engine.

. to meet high-speed work.

The drawings show the construction of a gasengine embodyingstationary cylinders 1, the rotative element being a crank-shaft 2. In this arrangement the cylinders are preferably water-cooled; but it is immaterial in view of the scope of my invention whether the cylinders are stationary or rcvolublc, as the pis ton-link connection is applicable to either case, and where the cylinders are mounted to revolve air-cooling is employed. The pistoncylinders are arranged in a common plane, with their axes radially disposed to the crankshaft and at ninety degrees to each other. These cylinders are supported by the crankcasing3, which is made in separate detachable parts 4. The casing 3 is provided with four circulanopenings arranged to receive the inner open ends of the cylinders. The halves of the crank-casing are suitably bolted together, and the cylinders may also be bolted to the casing.

The crank-shaft 2 is a finished forging with a single-throw crank which comprises double webs 5 and a crank-pin 6. The crank-pin and webs are preferably counterbalanced by weights 7. The crank-shaft is mounted in its casing and journaled in bushings 8 in the usual manner, and a fly-wheel 9 may be provided to establish the smooth operation of the engine. In the case of revolving cylinders the fly-wheel may be properly dispensed with, as the cylinders subserve the function of balancing the running of the engine. Trunkpistons 10 are best adapted to my invention. These afford within themselves space to contain the means for connecting the pistons with the particular form of linkage shown herewith, and they thereby contribute in reducing the distance between the center or axis of the crank-shaft and piston-heads.

Each piston is provided with a bridle 11,

which carries a wrist-pin 12. The wrist-pins are connected indirectly with the crank-shaft through an arrangement of links. This latter comprises a closed chain of barsor a parallelogram of toggle-links 13, which are jointed at the wrist-pins. A connecting-rod 14: connects one joint of the toggle-links with the crank-pin. By means of this arrangement those pistons which are disposed opposite each other move simultaneously in opposite direction and at the same speed, thus balancing the parts. The effect of the piston impulses uponthe toggle-links is to change alternately the diagonal dimensions, contracting one diagonal of the parallelogram of links and simultaneously elongating the other. The wrist-pin end of the connecting-rod is thus given a reciprocating motion, which in turn is converted into rotary motion at the crankpin end, and thereby rotates the crank-shaft.

The bridle 11 of each piston comprises a plate 15 and legs 16. In the ends of the legs the wrist-pins of the pistons are mounted. The attachment of the bridle to the piston is of such a nature as to permit of a limited movement thereof relatively to the piston. This is an oscillatory or tilting movement in the plane of the links, and its object is to prevent or equalize the side thrusts exerted upon the pistons, due to the power impulses of each piston working upon the others obliquely or in the direction of the individual links.

I have observed that in this type of engine should there be slight mechanical inaccuracies to cause any piston to fail to axially aline with its respective cylinderdue, for instance, to one or more of the members of the linkage beinglonger than the others-there would be undue wear at certain portions of the pistons and cylinders, causing them to get out of round. This tendency I have overcome by resiliently suspending the wrist-pins. so that slight unavoidable inaccuracies in the linkage do not affect the pistons in respect to causing their frictional wear with the cylinder, and thereby render them eventually leaky and otherwise imperfect.

A stifi' spring is employed to control the movement of the bridle and impart the proper degree of flexibility thereto. This spring is provided in the form of a spring-headed bolt 17, the shank of which passes centrally through the plate 15. The head of the bolt is a concaved spring, and the ends thereof impinge firmly upon the ends of the plate of the bridle, the proper degree of pressure tobe exerted by the spring being obtained by means of the nuts 18, secured .on the end of the bolt and engaging the head of the piston. On the exterior surface of theplate 15 is formed a rounded bearing-ridge 19, which is held in contact with the inner surface of the pistonhead by the bolt, and on this bridge the bridle as a whole tilts.

In order to prevent the bridle from turning on the bolt 17, interior lugs or studs 20 are provided on the piston-head. These are arranged on the opposite side of the bolt and are adapted to enter openings 21, located at the ends of the plate 15 adjacent the ends of the spring-head of the bolt. These lugs serve to guide the movement of the bridle, and by means of shoulders 22 they also limit the tilting of the bridle to one side or the other, as the plate 15 is adapted to abut upon these shoulders to arrest further tilting. The object of the spring-heads of the bolts is to exert a force tending to maintain the bridles in axial alinement with the pistons; but by rea son of the resiliency which they possess the wrist-pinsare permitted to assume different positions within operative limits to accommodate themselves to any change in the direction of application and magnitude of force from one piston to the others. By this means side thrhists upon the pistons. are largely distribute To suitably guide and center the togglelinks, the two opposite members thereof are pivotally mounted to operate as beams. As the points of the toggle-links or, in other words, the wrist-pins travel simultaneously exactly .in right-angular radial directions, the pivotal points of the two pivoted links constantly change their relative position by oscil-' lating about the crank-shaft as a center. For this purpose a movable supporting means is provided, to which the links are pivoted. The linkage is shown more clearly in the diagram Fig. 1. The broken lines a b and c d represent the radial direction of reciprocation of the wrist-pins or joints as the centering mem ber oscillates on the are c f described about the center 0. Since the links are of equal length and the center member is pivoted to two opposite links and itself centrally pivoted, there must be a constant relation between the joints of the links or, in other Words, they move exactly in right-'angularlydisplaced radii. The cylinders are similarly displaced, and thus perfect axial alinement between the pistons and cylinder is obtained. As shown in Figs. 2 and 3, this supporting means comprises a centering member or casing 22, which is mounted within the crank' The centering member cage, centrally of the ends, are arranged pairs of posts 2& at diametrically opposite points. The pivoted links are fulcrumed between these posts by pins 25. By this construction the cage and the parallelogram of toggle-links operate as a whole about the crank-shaft, while at the same time the links have an independent movement derived directly from the pistons.

The connecting-rod passes through an opening 2 6 in the centering member, in which it freely moves. By reason of assembling the pistons closel about the crank-shaft the open ends of the pistons are suitably cut away to provide clearance between the same and the cylindrical centering member at the ends of the outstrokes of the pistons. Also for the same purpose openings 27 are provided in the centering member for affording clearance for the projecting portions of the joints of the togglelinks, as shown by the top and bottom pistons, Fig. 2. The explosions are regulated to occur consecutively in the cylinders, so that the power impulses of the pistons produce, through the toggle-links and connecting-rod, continuous rotation of the crank-shaft. By employing a single-throw crank the turning moment of the crank is equivalent to a fourthrow crank-shaft having the cranks displaced about the axis at ninety degrees and the mechanism intermediate the pistons and crankshaft is much simplified and reduced in dimension. The linkage is also adaptable to other uses as, for instance, in connection with suitable pumping mechanism or it may be employed as a mechanical movement in=various adaptations.

In accordance with the provisions of the patent statutes I have described the principles of operation of my invention, together with the apparatus which I now consider to be the best embodiment thereof; but I wish to have it understood that the apparatus shown is only illustrative and that the invention can be carried out by other means.

WVhat I claim as new, and desire to secure by Letters Patent of the United States, is

1. In an engine, the combination of a central rotatable shaft, radially-reciprocating pistons, toggle-links connecting the pistons, and a rod operatively connecting the toggle-links and shaft.

2. In an engine, the combination of acentral single-throw crank-shaft, four radially-reciprocating trunk-pistons, wrist-pins therefor, toggle-links jointed to the wrist-pins of the pistons, and a connecting-rod attached'to one of the wrist-pins and crank-shaft.

3. In an engine, the combination of a central crank-shaft, four radially-reciprocating pistons, toggle-links jointed to the pistons, an oscillating centering member mounted on the shaft and pivotally connected to two opposite members of the toggle-links, and a connectingrod connecting one of the pistons with the crank-shaft.

4. In an engine, the combination of a central crank shaft, four radially reciprocating trunk-pistons, toggle-links connecting the pis-- tons, a cylindrical centering member mounted on the crank-shaft to have oscillating movement and pivotally connected to two opposite members of the togglelinks, and a connecting-rod extending through the centering member and connecting the toggle-links with the crank-shaft, said pistons being cut away at their open ends in an arc corresponding substantially to the curvature of the centering member.

5. i In an engine, the combination of a central crank-shaft, trunk-pistons, a bridle provided in each piston, the same comprising a plate and legs, a spring-headed bolt attaching the bridle to the piston, the spring-head of the bolt being arranged with its ends impinging upon the plate, a wrist-pin carried by the legs, toggle-links jointed to the wrist-pins of the pistons, and a connecting-rod operatively connecting one wrist-pin and crank.

6. In an engine, the combination of acentral crank-shaft, pistons, wrist-pins resiliently carried by the pistons, toggle-links connecting the wrist-pins, and means operatively relating the toggle-links with the crank-shaft.

7. In an engine, the combination of a central crank-shaft, pistons, wrist-pins therefor, resilientmeans permitting a slight independent lateral movement of the wrist-pins relatively to the pistons, links connecting the wrist-pins, and a connectingrod connecting one of the wrist-pins with the crank-shaft.

8. In an engine, the combination of a central crank-shaft, trunk-pistons, bridles movably suspended in the same, each bridle comprising a plate and legs," said plate having a rounded bearing-ridge medially arranged and guideopenings'at opposite ends of the plate, springheaded bolts securing the bridles in the pistons with the rounded ridges bearing upon the pistonhead, said spring-heads impinging upon the ends of the plate, interior guide-lugs on the head of the piston engagingin the opening of the plate, shoulders on the lugs form ing abutments for limiting the movement of the bridles, wrist-pins carried by the legs of the bridle, toggle-links connecting wrist-pins, and means connecting said links with the crank-shaft.

9. In an engine, the combination of a crankshaft, angularly-displaced cylinders, pistons therefor, means for transmitting motion from the pistons to theshaft, and a yielding medium between each piston and said means for reducing the effects of side thrust.

10. The combination of a rotatable shaft, a parallelogram of links, an oscillating means centering the links relatively to the shaft, and suitably-guided members connected with the joints of the links.

In witness whereof I have hereunto set my hand this 29th day of August, 1903.

JOHN G. CALLAN.

Witnesses:

DUGALD MoK. MoKILLor, JOHN J. WVALKER. 

